Fig. 5. Type I defects in chimeras generated with 2N ES^+/+ cells and 4N Ets2^db1/Ets2^db1 embryos. All images on the left are bright-field (BF) and GFP views of E7.75 chimeras generated by aggregations of GFP-positive 2N ES^+/+ cells with 4N Ets2^db1/Ets2^db1, 4N Ets2^db1/Ets2⁺ or 4N Ets2⁺/Ets2⁺ embryos. All images to the right are whole-mount in situ hybridizations of the conceptuses to their left, showing the expression profile of the genes indicated. (A) 2N ES^+/+4N Ets2^db1/Ets2⁺ E7.75 chimera showing normal development that is indistinguishable from its 2N ES^+/+4N Ets2⁺/Ets2⁺ counterpart (data not shown). (B-D) 2N ES^+/+4N Ets2^db1/Ets2^db1 E7.75 chimeras showing abnormal development with defects identical to those seen in E7.75 type I mutants, as judged morphologically and by T, Hex and Oct4 expression. Scale bars: 100 µm.